As can be seen from the fact that well known herb medicines such as ginseng, a bracket fungus of the genus Fomes and, the like contain organic germanium, recently, the use of germanium has been noted in medical treatment.
Usually, organic germanium is administered orally. On the other hand, inorganic germanium is locally applied to the skin in the form of a magnetic material for medical treatment by bringing it into contact with an affected spot of the skin and the like. For example, Japanese Patent Laid Open Publication No. 117187/1979 discloses germanium which is a metal piece in the form of a substantially circular small disk and is brought into contact with the skin by pressing it against the skin with a plaster or the like.
Although these germanium materials manifest analgetic and antiphlogistic effects such as therapeutic effect on stiff shoulders, lumbago and muscular ache, its mechanism has not yet been clarified.
However, there is an opinion that, when germanium is applied to a diseased part, it removes an abnormal electric potential of the human body by electron interchange to bring the body back to the normal electric potential because:
(1) germanium is apt to be positively charged due to escape out of the peripheral electron (i.e., germanium has a strong electrophilic properties); and
(2) a diseased part or a body part with stiffness or pain generally has an increased elect-ron potential.
Further, it is presumed that the above metal piece of germanium stimulates an affected spot of the skin by pressing it against the skin with a plaster or the like to manifest certain therapeutic effect.
In any event, even if the above metal piece of germanium is applied to an affected spot of the skin with a plaster or the like, the contact surface is a mere flat surface. On the other hand, the affected spot of the skin is very small. Therefore, it is difficult to concentrate stimulation by pressing on the affected spot and there is a possibility that the therapeutical effect of germanium can not be strongly manifested.
Then, Japanese Utility Model Laid Open Publication No. 133339/1983 discloses an improved device for medical treatment wherein germanium powder and activated charcoal powder are mixed and subjected to heat molding treatment such as sintering or the like to solidify the mixture into a molded article having fine uneven contact surface which can readily concentrate stimulation by pressing on an affected spot of the skin to improve its therapeutic effect. That is, this device is aimed at the improvement of the therapeutic effect of germanium by extending the active surface of germanium with utilizing electrical conductivity of activated charcoal in addition to concentration of stimulation. However, the fundamental effect on the human body is limited to the electrical activity of germanium alone and, therefore, its therapeutic effect is naturally limited.
On the other hand, some ceramics irradiate far infrared rays by absorption of heat energy when they are heated, and it has been known that, when the human body is exposed to such far infrared rays, they manifest various effects such as rise in deep subcutaneous temperature, angiotelectasia, enhancement of blood circulation and metabolism, mitigation of sensory nerves, regulation of autonomic nerves and the like.
The present inventors have sought such a far infrared ray irradiating ceramic, and have found that, when germanium is mixed with the ceramic and the mixture is molded integrally, the therapeutic effect can be improved and the scope of treatment can be extended.
Japanese Patent Laid Open Publication No. 180979/1987 discloses a heating element of a warmer for warming the human body to enhance metabolism thereof which is a sintered molded article of a mixture of a far infrared ray irradiating ceramic, an oxide of a specific metal such as iron, manganese, chromium or the like, and metallic germanium or germanium oxide. However, this heating element is used by heating with a nichrome wire heater or the like and is different from a device for skin contact medical treatment. Further, in this heating element, at most, 10 parts by weight of germanium is used per 100 parts by weight of ceramic.